[PATCH v4 05/11] Documentation: devicetree: brcmstb_nand: add BCM63138 and Cygnus/iProc

Brian Norris
2015-05-13T00:54:21Z

Add notes to describe how some SoCs integrate this NAND core a little
differently, and so we define extra compatibility strings and register
resources/names.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
---
v4: reworked to include all NAND + SoC info directly in the NAND controller
node

.../devicetree/bindings/mtd/brcm,brcmnand.txt | 48 ++++++++++++++++++++--
1 file changed, 44 insertions(+), 4 deletions(-)

diff --git a/Documentation/devicetree/bindings/mtd/brcm,brcmnand.txt b/Documentation/devicetree/bindings/mtd/brcm,brcmnand.txt
index 662c857e74fe..4ff7128ee3b2 100644
--- a/Documentation/devicetree/bindings/mtd/brcm,brcmnand.txt
+++ b/Documentation/devicetree/bindings/mtd/brcm,brcmnand.txt
@@ -12,9 +12,14 @@ iProc/Cygnus. Its history includes several similar (but not fully register
compatible) versions.

Required properties:
-- compatible : should contain "brcm,brcmnand" and an appropriate version
- compatibility string, like "brcm,brcmnand-v7.0"
- Possible values:
+- compatible : May contain an SoC-specific compatibility string (see below)
+ to account for any SoC-specific hardware bits that may be
+ added on top of the base core controller.
+ In addition, must contain compatibility information about
+ the core NAND controller, of the following form:
+ "brcm,brcmnand" and an appropriate version compatibility
+ string, like "brcm,brcmnand-v7.0"
+ Possible values:
brcm,brcmnand-v4.0
brcm,brcmnand-v5.0
brcm,brcmnand-v6.0
@@ -30,7 +35,11 @@ Required properties:
"flash-dma" and/or "nand-cache".
- interrupts : The NAND CTLRDY interrupt and (if Flash DMA is available)
FLASH_DMA_DONE
-- interrupt-names : May be "nand_ctlrdy" or "flash_dma_done"
+- interrupt-names : May be "nand_ctlrdy" or "flash_dma_done", if broken out as
+ individual interrupts.
+ May be "nand", if the SoC has the individual NAND
+ interrupts multiplexed behind another custom piece of
+ hardware
- interrupt-parent : See standard interrupt bindings
- #address-cells : <1> - subnodes give the chip-select number
- #size-cells : <0>
@@ -41,6 +50,36 @@ Optional properties:
v7.0. Use this property to describe the rare
earlier versions of this core that include WP

+ -- Additonal SoC-specific NAND controller properties --
+
+The NAND controller is integrated differently on the variety of SoCs on which it
+is found. Part of this integration involves providing status and enable bits
+with which to control the 8 exposed NAND interrupts, as well as hardware for
+configuring the endianness of the data bus. On some SoCs, these features are
+handled via standard, modular components (e.g., their interrupts look like a
+normal IRQ chip), but on others, they are controlled in unique and interesting
+ways, sometimes with registers that lump multiple NAND-related functions
+together. The former case can be described simply by the standard interrupts
+properties in the main controller node. But for the latter exceptional cases,
+we define additional 'compatible' properties and associated register resources within the NAND controller node above.
+
+ - compatible: Can be one of several SoC-specific strings. Each SoC may have
+ different requirements for its additional properties, as described below each
+ bullet point below.
+
+ * "brcm,nand-bcm63138"
+ - reg: (required) the 'NAND_INT_BASE' register range, with separate status
+ and enable registers
+ - reg-names: (required) "nand-int-base"
+
+ * "brcm,nand-iproc"
+ - reg: (required) the "IDM" register range, for interrupt enable and APB
+ bus access endianness configuration, and the "EXT" register range,
+ for interrupt status/ack.
+ - reg-names: (required) a list of the names corresponding to the previous
+ register ranges. Should contain "iproc-idm" and "iproc-ext".
+
+
* NAND chip-select

Each controller (compatible: "brcm,brcmnand") may contain one or more subnodes
@@ -74,6 +113,7 @@ Optional properties:
Each nandcs device node may optionally contain sub-nodes describing the flash
partition mapping. See partition.txt for more detail.

+
Example:

nand@f0442800 {
--
1.9.1